From the Department of Radiology at David Grant USAF Medical Center Travis Air Force Base in Fairfield, California (Drs Lewis and O’Brien), and the Department of Radiology at the University of California—Davis School of Medicine in Sacramento (Dr O’Brien). Dr Lewis is a radiology resident.

Disclaimer: The views expressed in this material are those of the authors and do not reflect the official policy or position of the US Government, the Department of Defense, or the Department of the Air Force.

In posterior reversible encephalopathy syndrome, autoregulation of the intracerebral perfusion is thought to be hindered during a hypertensive episode, resulting in vasogenic edema.1 Owing to a relative decrease in sympathetic innervation, the posterior circulation (posterior temporal, parietal, and occipital lobes) is most often affected.1-3 Common causes include preeclampsia or eclampsia, renal failure, autoimmune disorders, and chemotherapeutic drug toxicities. Patients frequently present with headache, nausea and vomiting, visual disturbances, or seizures.3 Symptoms and imaging findings typically resolve after management of the hypertensive episode. However, complications, including superimposed infarct, necessitate early detection and treatment.